There is always a risk of seizures when withdrawing from benzodiazepines. During withdrawal, the risk of seizures increases by the size of the tolerance. For example, a person dependent on 3mg of xanax per day is much less likely to have a seizure during treatment than a person dependent on 10mg xanax per day.
Benzodiazepine-dependent individuals may try a variety of methods to avoid the risk of seizures. For example, lowering tolerance slowly before treatment would decrease seizure risk. Also, some ibogaine treatment providers suggest that small doses of a benzodiazepine be given during the treatment as needed to prevent seizures